n6 Parasitic Arthropoda 
The different types of larvae represented in figure Si were formerly 
supposed to belong to different species but Blanchard regards them 
as merely various stages 
of the same species. It 
is only very recently 
that the early stage and 
the method by which 
man becomes infested 
were made known. 
About 1900, Blanch¬ 
ard observed the pres¬ 
ence of packets of large¬ 
sized eggs under the 
abdomen of certain mos- 
83. Dermatobia cyaniventris (xlj<). After Graham-Smith. qUltoeS from Central 
America; and in 1910, 
Dr. Morales, of Costa Rica, declared that the Dermatobia deposited 
its eggs directly under the abdomen of the mosquito and that they 
were thus carried to vertebrates. 
Dr. Nunez Tovar observed the 
mosquito carriers of the eggs and 
placing larvae from this source on 
animals, produced typical tumors 
and reared the adult flies. It 
remained for Sureouf (1913) to 
work out the full details. He 
found that the Dermatobia de¬ 
posits its eggs in packets covered 
by a very viscid substance, on 
leaves. These become attached 
to mosquitoes of the species 
Janthinosoma lutzi (fig. 84) which 
walk over the leaves. The eggs 
which adhere to the abdomen, 
remain attached and are thus 
transported. The embryo de¬ 
velops, but the young larva (fig. 82) remains in the egg until it has 
opportunity to drop upon a vertebrate fed upon by the mosquito. 
84. Mosquito carrying eggs of Dermatobia 
cyaniventris. After Sureouf. 
